ABSTRACT

This chapter summarizes the existing information connecting the main factors involved in embryo–endometrial or fetal–maternal cross talk, including cytokines, growth factors, prostaglandins (PGs), and microRNAs (miRNAs). It shows that blocking PG receptors on the membrane of the trophectoderm of mouse embryos produces a considerable reduction in embryo adhesion rates. Antiadhesion molecules appear to perform a temporary role in the regulation of blastocyst implantation. The concept of a dynamic microenvironment or niche among cultured embryos was confirmed, highlighting the advantage of a continuous transfer of messenger RNA (mRNA) cargoes via exosomes over an acute transfer of mRNA by the conditioned medium. In any case, it would be interesting to add exosome-encapsulated proteins with possible autocrine functions to the culture medium of preimplantation embryos and compare these results with the addition of the proteins alone. The fetal origin of adult disease (FOAD) hypothesis holds that events during early development have a profound impact on the risk of specific diseases in adulthood.